<script>

var str="Every man in the world! Every woman on earth!";

var patt=/man/g;

var str2=str.replace(patt,"person");

document.write(str2+"<br>");

patt=/(wo)?man/g;

patt.compile(patt);

str2=str.replace(patt,"person");

document.write(str2);

</script>

​